SID X-4.3.0 and DRI

[Christoph <ml133@netpole.com.br>]

Since 4.3.0 entered sid, DRI didn't seem to work anymore for several
different video cards. There are three related bugreports for
xlibmesa-dri and one of them suggested to patch one file, but the
author didn't try it.

I did try it and it worked. For that, the whole source needs to be
downloaded. The suggested patch had two changes, one of which the
patches from the debian packages already did. The file is

	xc/extras/Mesa/src/X86/common_x86_asm.S

Line 185 (after applying the debian patch) will read:

	MOVUPS  ( CONTENT( GLNAME( sse_test_dummy ) ), XMM1 )

This has to be removed and the following lines need to be inserted:

	PUSH_L  ( CONST( 0x3f800000 ) )
	PUSH_L  ( CONST( 0x3f800000 ) )
	PUSH_L  ( CONST( 0x3f800000 ) )
	PUSH_L  ( CONST( 0x3f800000 ) )

	MOVUPS  ( REGIND( ESP ), XMM1 )

I have no idea what I might have broken with this, but DRI seems to
work fine again.

The DRI stuff sources seem to be rather chaotic. My card is a tdfx
type which by version and debian package description should use
glide3. The file

	xc/programs/Xserver/hw/xfree86/drivers/glide/glide_driver.c

just includes <glide.h>, and I didn't find any -Iglide/ or -Iglide3/
to select the right version. There is a type ¨GrHwConfiguration¨ which
exists only for glide2. The installation of glide2 warned me that I
don't have any compatible card installed, so I'm expecting problems
later.

Hopefully, this will be fixed in a future version.

Christoph Simon